OK, here is the current status of the Robotron.
I plug it in and turn on the power switch. I hear the hum of the power supply as the machine fires up, the 3 LEDs on the power supply board all light up solid, and the numeric LED on the ROM board flashes with a “u” or a “c”, depending on how you look at it. There does not appear to be any kind of numeric pattern to the flashes.
The screen just displays a green screen with a strange pattern.
I have posted a video to YouTube that shows the LED on the ROM board and the screen. Here is the video of my sad Robotron:
Also, I have posted some pictures to Flickr of the inside of the machine, if you would care to look:
Oddly enough, one time when I fired up the game, the monitor still looked as it does in the video, but the machine was repeatedly playing the sound that it makes when you are at the high score entry screen.
I have the game’s instruction manual, and a set of the drawings for the game. (Not that I can make any sense out of the drawings, I have a very limited knowledge of electronics. Please keep that in mind if you make any suggestions.) In the instruction manual, it tells you that if the rug pattern does not appear, that one of the first things you should do is check the fuse F2 on the power supply board. I did this, and the fuse appears to be good as I got a tone on the continuity checker for my volt meter. However, on a whim, I took the fuse out of the board and touched the probes to the empty clips, and received a tone. Is that supposed to happen?